The five major watersheds in Iowa cover two thirds of the state. During the floods of 2008, they lost 351,000 metric tons of nitrogen to rivers, representing 20 percent of the Dead Zone inducing nitrogen load delivered to the Gulf of Mexico (from 2.8 percent of the land area in the Mississippi River basin). Extrapolating to the entire state: 560,000 MT was likely lost; this mass is 64 percent of the total mass of nitrogen fertilizer applied to cornfields alone, worth well over $500 million as fertilizer (~$38.50 per corn acre). Although 2008 was an extreme year, the nutrient fluxes observed were only twice the median rates.